Marrli, 1922. 



SCIENTIFIC AGRICULTURE 



217 



length of the column of milk or clot and 

 proceeding to the point where about half 

 of the contents of the tube remains undis- 

 solved. We have designated this dissolv- 

 ing as of the "lateral" t^'pe. Of this 

 group twelve cultures were isolated from 

 feeds and bedding; thirty strains were re- 

 covered from milk procured under asep- 

 tic conditions — four from fore milk, nine- 

 teen from middle milk, and seven from 

 strippings; the remaining eleven strains 

 of the group were recovered from air, mix- 

 ed milk, the milking-machine and butter. 



Constituting Group II, is another series 

 of cultures, twenty in number, the majority 

 of which appear to precipitate the casein 

 rather than to form a clot. When a clot is 

 formed it is soft and flaky in appearance. 

 Subsequent digestion is stratiform and 

 is not accompanied by any perceptible 

 odor. Of this group, one strain was iso- 

 lated from water, one from silage, one from 

 air, and seventeen from milk samples taken 

 under aseptic conditions; of the seventeen 

 cultures from milk, two were from fore- 

 milk, eleven from middle milk and four 

 from strippings. 



A third group — Group III — ■ includes 

 thirty-two cultures which digest the 

 milk. The digestion begins at the surface of 

 the milk or clot, continuing downward until 

 only a thick gelatinous fluid remains. A 

 pronounced putrid odor is noted in everj- 

 case. Of the thirty-two strains, twelve 

 were isolated from water, one from feeds, 

 six from air, four from the milking mach- 

 ine, and five from milk produced under 

 aseptic conditions — two from fore-milk, 

 two from middle milk and one from strip- 

 pings. 



Our fourth group — Group IV — in- 

 cludes the remaining twenty-eight cultures. 

 The reactions of these strains in milk are 

 so variable that Ave deem it undesirable 

 to attemjit a sub-division into further 

 groups. 



TABLE I 



The sources from which 133 "Milk-Dis- 

 solving" organisms have been isolated are 

 tabulated here, and the cultures are group- 

 ed according to the mode of dissolving. 



I— I E-^ 



1-. (-1 ^ 



g CU Cm CU P^ ^ 



3 p p o p ^ 



S 6 6 c c Eh 



Milk produced 



uijder Aseptic 



conditions ... 30 17 •") .j 57 



Air . 7 1 (i Ki 30 



Feeds & Bedding 12 1 1 2 16 



Water — 1 12 2 15 



Mixed Milk ... l _ 3 2 6 



:\Iilking-Machine. 2 — 4 — 6 



Butter 1 — 11 3 



53 



20 32 28 133 



It will be observed that the groupings as 

 specified above have been determined 

 primarily according to the reactions of 

 the organisms to milk. This procedure is 

 in harmony with the prime object of the 

 investigation. The reactions to milk and 

 the consequent groupings were recorded 

 when the cultures were newly isolated. The 

 continuity of the work was interrupted at 

 this stage, and a new laboratory was oc- 

 cupied and equipped. On the resumption 

 of the investigation, it was found that of- 

 the one hundred and thirty-three cultures 

 originally recovered, only seventy-eight 

 were available for further examination. Of 

 the seventy-eight strains thus remaining, 

 thirty-two are in Group I, eleven in Group 

 II, seventeen in Group III, and eighteen in. 

 Group IV. The seventy-eight cultures 

 have been examined microscopically, their 

 relation to the Gram stain determined and 

 their reactions to gelatin glucose and lac- 

 tose recorded. — See Table, page 219. 



The features of the thirty-two cultures 

 in Group I — the cultures which dissolve 

 milk laterally — are as follows: — 



(a) twenty-one strains are Gram positive 

 cocci, fermenting glucose and lactose to 

 acid, and liquefying gelatin. 



(b) five strains are Gram positive rods: 

 two strains ferment glucose and lactose to 

 acid and liquefy gelatine; one ferments 

 glucose and lactose to acid but fails to 

 liquefy gelatin; one ferments glucose and 

 lactose to acid and gas and liquefies gel- 

 atin; one ferments glucose and lactose, 

 to acid and gas but fails to liquefy gelatin^ 



